


Family Ties

by tiger_in_the_flightdeck



Category: Sherlock (TV), Star Trek: The Original Series
Genre: Case Fic, Crossover, Established Sherlock Holmes/John Watson, Fluff, M/M, Pre-James T. Kirk/Spock, Sherlock and Spock bonding over their captains, Time Travel
Language: English
Status: Completed
Published: 2016-01-07
Updated: 2016-01-07
Packaged: 2018-05-12 10:33:30
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,970
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5663110
Author URL: https://archiveofourown.org/users/tiger_in_the_flightdeck/pseuds/tiger_in_the_flightdeck
Summary: <blockquote class="userstuff">
              <p>While investigating some mysterious deaths, Bones comes up with the idea of seeking assistance from Spock's famous ancestor.<br/>Sherlock solves the case inside ten minutes, but finds it a good chance to learn as much as he can about Spock.</p>
            </blockquote>





	Family Ties

**Author's Note:**

  * For [Spookywanluke](https://archiveofourown.org/users/Spookywanluke/gifts).



> A prompt piece, I had a lot of fun with this, and finally got a chance to play with my own headcanon about Spock's lineage.  
> I just really love the idea of John being able to adjust to anything after he yells for a few minutes.

_ Captain’s Log, Stardate 3817.3 _

_ We have been called in to assist in an investigation of a series of mysterious deaths taking place on Balin. Officials there believe they have captured the assailant, but since the man has been in custody, three more individuals have fallen victim.  _

_ While the prisoner has given a full statement of confession, we have been asked to find any possible accomplices - _

“Jim?”

_ -or copycats that might be- _

“He is busy with his work. We can return another time.” 

“No, I want him to hear your idea.” 

“My idea? It was you that made the suggestion.” 

_ -carrying on with the slayings- _

“Well, you inspired it, then. Here, maybe if I just…” 

_ -in the capital of - Ow! _

 

Jim Kirk picked up the chess piece that had been thrown at the back of his head, and glared at it, then at the pair behind him. 

“Well, it certainly got your attention, Jim.” McCoy shrugged. In his hand was a second piece, ready to throw if the first hadn’t gotten his captain’s attention. He tossed it from hand to hand for a moment as if he was still considering tossing it across the room until it was plucked out of the air and returned to the board. 

“My knight was not in that position, Mr. Spock.” Jim pointed out with a small smirk. 

“Ah, yes. My mistake, Captain. I was thinking of the game that we are playing in my quarters.” 

Rubbing the back of his head, Jim pushed away from his console and stood. “Of course, Mr. Spock.” he said blandly, hiding a smirk. “What was this idea that one of you may or may not have had?” He put the piece he held back on the board. 

“You know how Spock here is always bragging about his famous ancestors?” 

“I wasn’t aware that it was boastful to discuss my lineage,” Spock put in before Jim could reply.  

Jim put up his hand to stop the argument in its tracks before it had a chance to go any further. “Fine Bones, what about his family?” 

“That detective fellow he descends from. Supposed to be the cleverest man of his time. Do you see what I’m getting at…?” 

 

_ Captain’s Log, Continued _

_At the advice of our Chief Medical Officer, which I had initially thought to be a joke, we are looking into the possibility of bringing in Mr. Spock’s ancestor, the consulting detective, Sherlock Holmes. _

 

“These were nice boots.” John complained, hauling himself up the muddy bank. He tried his best to avoid putting his gloved hands down for support, which almost resulted in an arse first trip back down the bank. 

They were on a case in the West Country, and Sherlock claimed to have solved it within ten minutes of stepping off the train. Gathering the evidence had proved to take considerably longer. For John, at least. Sherlock was standing at the top of the bank, wandering around in circles with his mobile above his head trying to find a signal while John fished a sodden coat out of the pond. 

“They were knock offs.” Sherlock replied, giving his mobile a shake and holding it up higher. “And not very good ones at that.” He gave up with his phone and shoved it into his pocket. Sherlock clucked his tongue and reached a long arm out to grab John by the front of his jacket to haul him up beside him. “Honestly, John, you just need to dig in your toes and lean forward.” 

“Easy for you to say; you can just take one step and you’re at the top.” John huffed out. He smoothed down the front of his jacket with a dignified sniff. “Two, at most.” 

Sherlock mostly ignored him in favour of crouching in the mud with no regard for his jeans, and rifled through the pockets of the wet coat. John looked on, holding the torch for him and humming quietly to himself. Despite the changes in their relationship in the past few months, Sherlock still never shared information on cases. By now, John was certain that it was so he could proudly give the big reveal at the end of the case. A wordless ‘Ta da!’ before John’s praise and applause. 

With a grunt of disgust, Sherlock thrust the coat away from him and rocked back on his heels. “Nothing!” he snarled and stood up. Sherlock paced in place for a moment before something in the distance caught his attention. “Give me your torch. I saw a light on the other side of the hedgerow.” 

Following on Sherlock’s heels, John stepped gingerly through the mud, almost hopping from dirt clod to dirt clod to save his boots any more damage. “It’s probably nothing, Sherlock. Let’s go back to the inn and start fresh.” John knew Sherlock wouldn’t agree, but he just didn’t want to end the night by walking up on a middle-aged Cornish couple dogging in the cramped confines of a Datsun Cherry. 

Again. 

Sherlock pushed his way through the hedge and reached back to hold a few branches out of the way to help John through it. When they were through to the other side, Sherlock pulled himself up short when he saw three men that had definitely not been there before. 

John swore under his breath when he ran into Sherlock’s back and almost toppled back into the hedge. “What the hell?” he snapped and looked around Sherlock. Seeing the men, he schooled his features and stepped out in the open. “Sorry, hi. Are you lost?” All three men seemed to be wearing shirts that were matching, if in different colours, like a work uniform of sorts. 

“Which one is he?” McCoy asked, looking from one man to the other. 

Spock leveled him with a chilly stare and folded his arms over his chest. 

Not entirely sure why, John felt insulted by the expression on the man’s face, what little of it he could see in the darkness. “You’re looking for Sherlock.” It wasn’t a question, and John tucked his hand into the curve of Sherlock’s arm, drawing him away. The trio might look like they were going to start singing about getting your five a day on BBC Kids, but it was the middle of the night in a field. It wouldn’t hurt either of them to be careful. 

“I’ll take that as confirmation.” The man who had spoken first held up a mobile. 

“There’s no signal out here.” Sherlock told him over John’s head from where he had been shepherded between him and the hedgerow. “I’ve already tried.” 

“I’d wager I get one.” he chuckled and pressed a button. 

There was a high, droning whine and John clapped one of his hands to his ear, but didn’t let go of Sherlock’s arm even as a bright light surrounded them. He held Sherlock in a powerful grip as it felt like the world fell away from their feet. 

  
  


_ Captain’s Log, continued; _

_ Our guests have adapted to the Enterprise with surprising calm. We hadn’t planned on bringing both men, but it seems that Sherlock Holmes’ companion is passionately protective. His friend, Dr. John Watson, is far calmer than our Science Officer’s ancestor, given the situation.  _

_In fact, after indulging in several minutes of shouting and swearing, Dr. Watson appears to only be distressed by the fact that Mr. Spock is Sherlock’s descendant. _

 

“No, I’m serious Sherlock.” John snapped as he paced in spot. 

After being beamed aboard the ship, Sherlock had promptly sicked up on John’s front. Now, several hours and a hurried explanation later, John was wearing one of the doctor’s shirts, and he looked like he had been a member of the crew all of his adult life. 

He was glowering at Sherlock, who was standing almost toe to toe with Spock with his head tilted to the side. 

John had to admit- grudgingly- that the pair had plenty in common. The same sharp lines of face, the same intelligent eyes. 

“Yes, I know you are. You’re using your Serious Voice.” Sherlock said, his nose crinkling up and his head tilting to the other side. 

“Don’t be a dick.” John sighed and crossed the bridge to take Sherlock by the hand, lacing their fingers together. “This man is your descendant. That means that-” 

“That I will have children. Or, child at least. Yes, I understand that. You are angry with me for something that hasn’t even happened yet.” 

John pressed his lips into a tight line before squeezing Sherlock’s fingers. “And that’s another thing.” He shot this at the three men that had come to collect them. From what he could understand, and he was still a little hazy about these details, they were orbiting the Earth in the present, and the ship had come from a few hundred years in the future. “Aren’t you risking altering your timeline?” 

“Don’t be ridiculous, John.” Sherlock rolled his eyes but caressed John’s fingers with his thumb in return. “If they traveled back through time, that means that whatever happens from here out, would have happened. Because the events are part of our own time line. Which means that if I do this-” Sherlock checked John with his hip, nearly knocking him down. Before John could return the attack, Sherlock beamed and kissed him lightly on the lips. “Then those actions are part of what will eventually lead to these men coming back to find us.” 

With a quiet grumble, John kissed Sherlock back and huffed. “Well, aren’t you the smart duck?” 

“Which brings us to what we need.” Jim was grateful to finally have a place to step into the conversation. It looked like the two men would happily argue forever if he didn’t interrupt. “We would like to hire your services. We have recreated the most recent crime scenes for you to investigate.” 

  
  


Sherlock was fascinated by the holodeck recreation of the scene. He spent the first several minutes simply touching things with a look of wonder on his face. Kneeling in simulated sand, Sherlock examined the first body that he was shown. 

“The body doesn’t appear to have any injuries.” Spock told him, kneeling down beside him. “Each victim was the same, and all were in this position when they were found.” 

The body, largely humanoid, was in a foetal position with the knees drawn up and a peaceful expression on the face. The eyes were closed and the lips slack. 

John stood behind them both, taking notes, and admiring Sherlock. Seeing him beside Spock was disorienting, but Sherlock seemed to be in his element. He spoke animatedly, his hands moving in the air as he gave his deductions. It was an interesting comparison to the minimalistic, calculated movements of Spock. 

While the rest looked on, Spock instructed the holodeck to show the next body. Just as he had said, it was in the same position as the first, with the same vacant expression to the face. The only difference appeared to be the direction the body was facing. The first had lain on its right side with its head to the North, the second on its left facing South-East. 

In his notepad, John made a few sketches of each body and the stones around them. He was sure it wouldn’t be needed, but it was the only assistance he felt capable of giving, beyond occasionally praising Sherlock for his observations. When he crouched down to try to examine the holographic body, he earned a sharp stare from two alarmingly similar pairs of eyes. That they were different colours didn’t seem to matter when they were both unmistakably telling him to not be an idiot and step away. 

“Maybe we should just leave them to it.” John muttered as he stood back and fell into line with Jim and McCoy. “Sherlock has his methods for this sort of thing, and it’s best not to try to interfere with them.” John let  _ Or he might throw a tantrum _ hang in the air, unspoken, but understood. With a little roll of his eyes, John followed the men back to the bridge. 

He may have been appalled by Sherlock’s lack of understanding about the basics of the solar system, but he would never consider himself a space nut. None of that mattered to him when he stepped up to the glass and looked down on the Earth. They were orbiting above the South Pacific, and the skies were clear. He could see tiny dots of tropical islands and coral atolls, and for a moment he thought his knee might buckle at the impossibility of what he was experiencing. John supposed that many people would feel tiny and insignificant at a moment like this, circling so high above the planet that he could track weather patterns and storm systems over thousands of kilometers at a glance. It wasn’t the case for him. He was there looking down on the world because he and Sherlock would live on in memory and deed, even centuries after their deaths. The words he had put down, his records of Sherlock’s skills and abilities, would prove to immortalise them. 

“Sherlock will be livid,” he murmured aloud, then grinned. 

 

“It’s not murder.” Sherlock declared when he finished his examination. He rocked back on his heels and stood up, brushing off his knees. 

“I suspected as much, myself. Not least of all because several of the victims died after the suspect was in custody.” 

Sherlock rolled one of his shoulders and ran his fingers back through his hair. “It wouldn’t be the first time I’ve seen someone kill from behind bars. It is possible that it was a delayed action poison, or an internal injury. The final victims could have been given the poison or a blow the day your suspect was arrested.” He flapped his hand in the air to dismiss his own argument. “Regardless, these… individuals…” Sherlock cleared his throat, showing his distress over the situation for the first time. “None of them were murdered. All of the deaths were natural. It is likely an end of life ceremony of sorts.” 

“We will need to look into past mass deaths on the planet.” Spock nodded while leading Sherlock out of the holodeck. “Would you care to join me? I think you would be interested in our computer systems.” 

“I suppose there’s no harm in leaving John alone with your crew for a while. I don’t imagine he could get in much trouble on an enclosed ship.” 

In Spock’s sparse quarters, Sherlock perched up on a chair to watch over his shoulder as he spoke to the computer. The technology was fascinating, and reminded Sherlock of afternoons spent watching John losing an argument with Siri on his new mobile. 

“Computer, access instances of mass deaths on planet Balin going back five hundred years.” Spock instructed the system. 

It returned after several minutes with the information they needed. Over the past five centuries, a small religious group had a ceremony every year to mark the end of life for its followers. Those that knew their time was coming to a close, would arrange to have their final day in comfort and happiness, with their body left to the elements. The religion was mostly followed by those in the lower classes, and after a cultural upheaval a hundred years earlier, had gone almost completely underground. It was only in the last year that they began to come out of hiding.

“Well, that would explain why those in charge of the investigation wouldn’t have been able to make the connection.” 

Spock agreed, humming thoughtfully as he leaned back in his chair with his arms folded over his chest. “That doesn’t explain why the prisoner has confessed to the killings, when there weren’t any killings to speak of.” 

Leaning forward, Sherlock rested his elbows on his knees and ran his fingertips over his bottom lip and his chin as he considered it. “It’s entirely possible that he is a martyr, trying to keep the authorities from sniffing around his religion by sacrificing himself to be seen as a murderer.” He clicked his tongue over his teeth. “Or, he’s a twit that wants to make a name for himself. It’s a common enough thing on Earth. It stands to reason it would happen elsewhere.” 

Satisfied with an interesting job well done, Sherlock clapped his hands together and made a pleased little sound. “So,” he drawled, looking Spock over with a critical eye. “You believe that I am your… great grandfather. Fascinating.” 

“Fascinating, Mr. Holmes?” 

“Sherlock, please. No one calls me that unless they are arresting me.” Sherlock chuckled and pushed himself up from his seat on the bed. He paced the room, humming to himself as he looked around. With a victorious whistle, he pressed a button on the underside of desk near the drawers. The bottom drawer clicked open, and Spock jumped. “You were concealing it with your knee. A simple enough thing.” Sherlock explained. From the drawer, he withdrew a slim, book-like folder. He flipped it open and was amused to see that Spock’s cheeks tinged slightly green when he saw two photographs. They were crisp, with brilliant colours. The first showed two adults standing together, lightly touching their fingertips together. The other showed the same couple, a few years older, with a small boy sitting in front of them with a grumpy expression on his little face. Hugged to his chest was a chubby, furry creature with sabre teeth that had its face tilted up to press it nose to the underside of the boy’s chin in an animal’s kiss. It reminded Sherlock of so many of his own family photos from his childhood. It was the woman in the photos that made him smile fondly. 

“Interesting, is it not, that your father, who is clearly not human, is the one that gives you your looks and much of your personality. And your mother…” Sherlock touched the photograph, tracing the image for a moment. A round, expressive face, and kindly blue eyes with an obvious gleam of wicked humour glinting in them. Sherlock cleared his throat and set the folder back into the drawer. 

“Why is your friend so angry at the thought that you will have children?” Spock asked, not understanding the gesture. He reached into the drawer to set the small photo album more safely under a stack of personal papers. 

“John… Is not my friend.” Sherlock murmured, returning to his circuit of the room. 

“You seem to be close.” 

“Friend is not the proper term.” Sherlock explained, clasping his hands behind his back in an unconscious mimic of John’s military stance as he walked. 

“T’hy’la,” Spock murmured.

“Hmm?” Sherlock looked up from the elaborate chess game that he was examining, and noticed that Spock was resting his hand his abdomen and for a moment Sherlock was dismayed to think that the concept of a relationship between him and John would make Spock feel physically ill. But the wistful expression that flashed across his features banished that concern. “Ah, I see. Your own word for it.” Sherlock returned his attention to the chess game, moving a piece. “Your captain certainly is an attractive man.” he said lightly and moved two more pieces before straightening up again. 

Lips pursed into a tight line, Spock arched up an eyebrow. “You are welcome to your opinion on the matter.” he said in a flat dismissal. 

Sherlock chuckled to himself in that strangely silent way of his and stepped away from the chess set. “You sound like my John when he is about to throw a tantrum of his own.” 

Spock pushed himself to his feet and switched off the computer. He strode past Sherlock but waited for him at the door. “We had best collect your t’hy’la, to ensure you both return safely. Not to sound overly dramatic, but my existence does depend on your ability to breed in the near future. Your future, my past.” For the briefest moment, Spock looked flustered and he folded his arms more tightly across his chest before marching down the corridor. 

“Oh, there you are.” John grinned when he saw Sherlock and Spock approach the bridge after a cheerful whistle announced their presence. He held his hand out to Sherlock, beckoning him with his fingers. 

A red clothed ensign had brought him his freshly cleaned shirt, but there was a small pin fixed to the front that matched that worn by the crew members. John buffed it with the cuff of his sleeve and beamed. 

“You look pleased with yourself,” Sherlock murmured, lacing their fingers and tipping his head down to brush a kiss behind John’s ear. 

“He helped us to communicate with an Earth aircraft that had caught us on their radar.” Jim explained with a lopsided smile. Seeing the two of them so affectionate and tender with one another, Jim imagined that it was what it could be like with Spock, if he would ever let go of the inner battle between human passion and emotion, and cold Vulcan tradition. This Sherlock Holmes looked to be at ease with a comfortable balance between the two. 

The guests stayed on for three more days. John explored the ship, and spent hours in the sick bay watching the procedures in amazement. Sherlock took lessons on the Vulcan lyre, and learned to swear in several different alien languages. 

“Let me keep the curses.” Sherlock asked quietly when they were waiting to have their memories erased. “And the music. I want to translate it to violin. It won’t do any harm.” 

  
  
  


Sherlock woke in bed with John, his head pillowed just below the scar on his chest. He wasn’t sure why they were dressed, but it wouldn’t have been the first time they had stumbled into bed, dog tired after a case, only to realise in the morning that they were still in their jeans and muddy boots. 

“Mmmorning, Sherlock.” John moaned happily, tightening his hold around Sherlock’s shoulders. He pressed a kiss to the top of his head and roll out of bed, creaking and groaning. Something was stabbing at his chest, so he grunted and looked down. He tugged a pin off his shirt and tossed it into his duffel bag. It was a pretty little thing, but he couldn’t recall where he’d picked it up. 

“What’s that you’re humming?” he called from the sink, his mouth full of toothpaste ten minutes later. 

Sherlock paused in the middle of his song and hesitated. “I… I’m not sure.”

“It’s lovely, whatever it is. You should write it down when we get home.” 

The rest of the day, Sherlock avoided packing, watched John fuss with his clothes, and wondered how to delicately broach the subject of considering surrogacy after they got married. 

  
  
  
  


_ Captain’s Log, Stardate 3825.7 _

 

_ I have had a word with our Medical Officer McCoy about the recklessness of coercing his captain into travelling through time simply to tease our Science Officer. Since the events with She rlock Holmes and his companion John Watson, Mr. Spock has requested a personal furlough to visit with his parents the next time we are in the vicinity of Vulcan. He refuses to elaborate beyond stating that he wishes to speak with his mother about something. When I press him for more answers, he feigns deafness and plucks at his lyre.  _

_As this will be a very good time to resupply and give many of the crew members shore leave, I have submitted a formal request for approval. _

_ Dr. Watson left his mobile device aboard ship, and Lieutenant Uhura has taken it as souvenir of antique communication technology. She has also uploaded the music files to the ship’s computer. We all hope she tires of it soon.  _


End file.
